feat(kernel): static-first reviewer gate (role-reliability §5)

Run operator-configured static-analysis commands (compiler/detekt/formatters) as a
deterministic harness step on the producing stage, before the LLM reviewer. A stage
declares `static_analysis = [commands]`; after it produces its artifact, each command
runs in the workspace root and the results are recorded in a StaticAnalysisCompletedEvent
(invariant #9 env observation — recorded live, folded on replay, never re-run). A
non-clean command fails the stage retryably with its output fed back verbatim (§2:
compiler/test output is ground truth), so the implementer fixes it and only static-clean
code ever reaches the reviewer. This makes §5's "reviewer context excludes static findings"
mechanical — the findings are resolved upstream, so the reviewer can't waste inference on
what detekt catches for free; no output-parsing, no context plumbing.

- StaticAnalysisCompletedEvent + StaticAnalysisFinding (core:events) + registration.
- StaticAnalysisRunner seam + ProcessStaticAnalysisRunner (whitespace-split argv, stderr
  merged, timeout→nonzero exit) in core:kernel; wired (nullable) into OrchestratorEngines
  and the server. Null runner / no workspace root → logged no-op, never blocks the run.
- StageConfig.staticAnalysis + `static_analysis` TOML field; runStaticAnalysis folded into
  a runPostStageGates sequence (produces → grounding → echo → static analysis).
- Documented `static_analysis` on the role_pipeline implementer stage (commented; commands
  are workspace-specific). The reviewer prompt half shipped in 3467826.

core/transitions/src/main/kotlin/com/correx/core/transitions/graph/StageConfig.kt

@@ -23,5 +23,10 @@ data class StageConfig(
     // the declared set is scope creep — the dominant local-implementer failure — and is
     // blocked by the plane-2 ManifestContainmentRule.
     val writeManifest: List<String> = emptyList(),
+    // Operator-configured static-analysis commands (compiler/detekt/formatters) run as a
+    // deterministic harness step after this stage produces its output (role-reliability §5).
+    // A non-clean command fails the stage retryably with its output fed back, so only
+    // static-clean output reaches the downstream reviewer. Empty = no static-first step.
+    val staticAnalysis: List<String> = emptyList(),
     val metadata: Map<String, String> = emptyMap(),
 )